In convert_nontype_argument to reference type we were inappropriately checking value_dependent_expression_p on an expression that might be a VAR_DECL and might be a TEMPLATE_PARM_INDEX of reference type. It's inappropriate in the former case because we don't care about the value of the object, only its address; we only want to test for the latter case. Tested x86_64-pc-linux-gnu, applying to trunk.